4 billion years ago the temperature was much higher due to repeated volcanoes and hot gases present in the atmosphere. There weren't any live forms on earth. ... The atmosphere had a different concentration of gases on the earth. There were no life sustaining gases.
Answer:
<u>Option- D: </u>Is the best choice to choose from the given options.
Now, let us explain the term Cell cycle in a more comprehensive way.
<u>As the cell cycle is controlled at three checkpoints.</u>
- The integrity of the DNA is assessed at the G₁ checkpoint.
- Proper chromosome duplication is assessed at the G₂ checkpoint.
- Attachment of each kinetochore to a spindle fiber is assessed at the M checkpoint.
Explanation:
The cell cycle is controlled by three internal checkpoints that evaluate the condition of the genetic information.
- <u>The G₁ Checkpoint</u>:This stage determines whether all conditions are favorable for cell division to proceed. The cell can halt the cycle and attempt to remedy the problematic condition, or the cell can advance into G₀ (inactive) phase and await further signals when conditions improve.
- <u>The G₂ Checkpoint:</u> The most important role of the G₂ checkpoint is to ensure that all of the chromosomes have been accurately replicated without mistakes or damage.
- <u>The M Checkpoint:</u>It occurs near the end of the meta-phase stage of mitosis. it determines whether all the sister chromatids are correctly attached to the spindle micro-tubules
Answer: condition intersex
Explanation: what causes this is unknown, it's been linked to manmade, environmental chemicals that block or mimic sex hormones.
This reaction is called a synthesis.
It represents the cycle of life, because a tadpole should turn into a frog.
